Car coupler



Nov. 5, 1957 W. J. METZGER CAR COUPLER 3 Sheets-Sheet '1 Filed May 11, 1953 I INVENTOR. W/LL/AM J METZGBQ BY ATTORNEY Nov. 5, 1957 w. J. METZGER 2,312,075

CAR COUPLER 1 Filed May 11, 1953 3 Sheets-Sheet 2 Z0 My 44 K INVENTOR.

WILL/AM J METZGER BY A TTORNEY Nov. 5, 1957 w. J. METZGER CAR COUPLER 5 SheetsSheet 3 Filed May 11. 1953 INVENTOR.

. W/LL/A 'J M5T20R BY figad ATTORNEY nited States Patent t is CAR COUPLER William J. Metzger, East Cleveland, Ohio, assignor to National Malleable and Steel Castings Company, Cleveland, Ohio, a corporation of Ohio Application May 11, 1953, Serial No. 354,217

16 Claims. (Cl. 213-126) This invention relates to couplers for railway cars and more particularly to means for preventing the lock of the coupler from being inadvertently returned to lock-set position after it has been removed from lock-set position during uncoupling operations.

This invention concerns the type of railway car coupler having a pivoted knuckle, a horizontally disposed knuckle thrower, and a vertically movable lock for securing the knuckle in locked position. The invention is adapted primarily for use with a coupler having a slot or recess in the guard arm side of the head for receiving an end portion of the knuckle thrower. During the switching of railway cars, as occurs in railroad classification yards, or during shunting of cars when trains are being assembled or disassembled, the lock of one of two coupled couplers is raised to lock-set position Whenever cars are to be separated. This permits opening of the knuckle and uncoupling of the couplers. In the lock-set position of the lock, the latter is out of locking relationship with the knuckle and has a lock-set seat which rests on the top surface of a portion of the knuckle thrower. The knuckle is then free to swing to open position and as it is swung to such position, a bearing surface on the top side of the knuckle tail slidably engages a bearing surface on the under side of the lock and moves the latter in a forward and upward direction to take it ofi the thrower and thus ofi lock-set position. Thereafter the lock is supported solely on the knuckle tail bearing surface until the knuckle is moved to closed position, at which time the lock drops to normal locking position.

It has been found that if the coupler is subjected to a sudden longitudinal impact after the lock has been taken off the aforementioned lock-set position, the lock will sometimes be thrown back to lock-set position. This has been found to be especially true when cars are brought together for coupling. As the couplers on the approaching cars engage and the open knuckle of a given coupler is suddenly closed, the lock, instead of dropping to locking position, will sometimes be thrown back to lock-set position, leaving the closed knuckle in unlocked condition. This failure of the couplers to couple properly is highly undesirable.

A reason for the lock being thrown back to lock-set position is that in existing couplers there is a lack of any substantial difference in elevation between the lock-set seat on the lock and the lock-seating surface on the knuckle thrower when the lock has been taken off the lock-set position upon opening of the knuckle. Another reason is that in this position of the parts there is substantially no longitudinal clearance between the lock-set seat on the lock and the adjacent thrower. The lack of longitudinal clearance results from the frictional drag occurring between the lock-set seat on the lock and lock-set seating surface on the thrower as the lock is taken olflock-set position. This frictional drag causes a slight clockwise rotation of the thrower, thereby moving the lock-set seating surface on the thrower in a forward direction while the lock is being taken off of lock-set position by the tail 2,812,075 Patented Nov. 5, 1957 of the opening knuckle. Consequently, the lock-set seat and lock-set seating surface remain in close longitudinal proximity to one another after the lock has been taken 01f lock-set position and a sudden longitudinal impact applied to the coupler may cause the lock, as it rests on the knuckle tail of the knuckle, to be thrown upward and rearward onto lock-set position.

It is, therefore, an object of my invention to correct the aforementioned difliculties by providing means to prevent the lock of .a car coupler from inadvertently being thrown back to lock-set position once it has been taken off this position.

Another object of my invention is to provide in a car coupler means to elevate the lock-set seating surface on the knuckle thrower substantially above the lock-set seat on the lock after the lock has been taken off lock-set position.

A more specific object of my invention is to provide a coupler construction having a rockable knuckle thrower whereby upon movement of the coupler lock off lock-set position the thrower assumes a rearwardly rocked position in which the lock-seating surface on the thrower is elevated to a position substantially above the lock-set seat on the lock.

A further object of my invention is to provide means which will resist movement of the lock-seating surface on the knuckle thrower of a coupler in a forward direction as the lock is taken off lock-set position by the opening of the coupler knuckle.

Other features and advantages of the invention will be set forth in the following description, taken in conjunction with the drawings, in which:

Fig. 1 is a longitudinal vertical sectional view of a coupler embodying the invention, showing the parts in locked position.

Fig. 2 is a transverse vertical sectional view of the coupler.

Fig. 3 is a horizontal sectional view of the coupler showing the parts in locked position.

Fig. 4 is a view similar to Fig. 3 but with the knuckle and lock of the coupler removed, the knuckle thrower being shown in reposed position.

Fig. 4a is a fragmentary horizontal sectional view of the coupler head.

Fig. 4b is a fragmentary vertical sectional view taken along line 4btb of Fig. 4.

Fig. 5 is a partial view in longitudinal vertical section showing the lock in lock-set position, with the lock lifter mechanism parts being shown in reposed position.

Fig. 6 is a partial view, similar to Fig. 5, but showing the parts of the coupler in the position corresponding to full knuckle thrown position, the lock lifter mechanism being shown in reposed position.

Fig. 7 is an enlarged sectional view taken along line 77 of Fig. 3 showing the position of the knuckle thrower when the lock is in either locked or lock-set position, the. lock for purposes of clarity not being shown.

Fig. 8 is a partial View, similar to Fig. 7, but showing: the position assumed by the knuckle thrower after the: lock has been taken off lock-set position.

Fig. 9 is a vertical sectional view taken along line 9-9 of Fig. 4.

Referring to the drawings, the coupler comprises the head 10 having a guard arm 11, knuckle 12, locklifter mechanism 16, lock 18, and horizontally disposed knuckle thrower 20.

The coupler head 10 is provided with the usual upper and lower ears 22 having aligned vertical openings 24 therethrough for reception of the usual knuckle pivot pin 26. Side walls 28 and 29, top wall 36 and bottom wall 31 of the head form therebetween the usual interior chamber 32 for reception of the operative parts of the coupler. Side wall 29 of the head is provided with a recess or slot 33 for receiving the end of rearward arm 34 of the knuckle thrower. Numerals 36 and 37 designate bearing pads formed on bottom wall 31 of the head which support the knuckle thrower in all of its operative positions. The constructionand function of these pads will beset forth'in a succeedingpart of this description:

The knuckle l-2 is o'f conventionalconstruction except that the top lock bearingsurface 38 (Figs. 2-and'3) of the knuckle tail 39, instead of being horizontal, is prefe'rably sloped laterally of the knuckle tail downwardly toward the knuckle side of the coupler head. It will be understood that'this surface supports the lock as the knuckle is swung to open position after the lock has been placed in lock-set position. Accordingly, the downward slope of surface 38'willcause the lock to move progressively'lower during opening of theknuckle.

The knuckle thrower 2(lis also of conventional construction except that'the forwardend portion of the top. surface of forward arm 40 of the thrower has been tapered towards the end of the arm, as at 40a (Figs. 7 and 8), to provide adequate clearancebetween this surface and the bottom surface 41 ofthe knuckle tail. The end of arm 40 bears against pad 19 on the knuckle to swing theknuckle to open position in the usual manner when the thrower is actuated. The thrower is pivotally mounted in the coupler head by means of upper and lower vertical trunnions 42 and 43, respectively. Adjacent'upper trunnion 42, the coupler head is formed with a knuckle thrower retaining lug 44. Lug 44 is provided with an arcnate bearing surface 44a for engagement with trunnion 42 to support the latter upon actuation of the thrower, to open the knuckle. Lower trunnion 43 extends into opening 45 in bottom wall 31 of the 'head and positions the thrower in chamber 32.

The lock 18 in locking position, as shown in Figs. 1, 2 and 3, rests on laterally extending shelf 48 on the knuckle, tail and is in engagement with side wall 29 of the'head and face 50 on the knuckle tail. In addition, the lock, when in locking position, is partially supported by arm34 of the knuckle thrower. Leg 52 of the lock extends into opening 53 in the lower portion of the coupler head and is pivotally and slidably connected to locklifter link 54 by means of trunnion 55 which is received in the upwardly and rearwardly sloping slot 56 in the lower end of the leg. The remainder of the lifter mechanism comprises rotor lever 57 which is pivotally connected at one end to link 54 by means of pin 58 and rotor member 59 to which the other end of lever 57 is connected for rotation therewith. Member 59 extends transversely of the coupler and is pivotally mounted in depending walls 60 on the coupler head. An uncoupling rod (not shown) is connected to member 59 for actuation of the lifter mechanism.

Pads 36 and 37 have been so positioned and arranged in relation to each other as well as to the center of gravity of the thrower 20 that when the lock rests on thrower arm 34, as in the locking or the lock-set position of the lock, the thrower assumes a generally forwardly tilted position, as shown in Figs. 2 and 7. In this position of the thrower the end portion of rearward arm 34 rests on bottom surface 33a of recess 33 in the head. When the lock does not rest on thrower arm 34, which occurs when the lock is in any position other than locking or lock'set, the thrower assumes a generally rearwardly tilted position, as shown in Fig. 8. In the latter position of the thrower, arm 34 is elevated with respect to surface 33a. Thus the thrower is rockable generally about an axis which is located approximately along line x-x, as seen in Fig. 4. The center of gravity of the thrower has been indicated as being approximately at G, and it will be clear that when the thrower is free of the-weight of the lock it will rock in a generally rearwarddirection about line x-x.

The plovision of a rockable thrower-in the manner above described constitutes an important feature of my invention. Support pad 36 is formed on bottom wall 31 of the coupler head, commencing adjacent side Wall 28 and extending in a diagonally reanvard direction into chamber 32. Pad 36 underlies one end of the knuckle thrower 20 with at least a portion of the thrower remaining in engagement with the top surface of the pad at all times during operation of the coupler. As seen in Figs. 2 and 9, the top surface of the pad is sloped downwardly from wall 28 in a direction lengthwise of the pad, as at 360, and also as seen in Figs. 7 and 8, downwardly in a generally rearward direction as at 36b. Support pad 37, also formed on the upper side of bottom wall 31, surrounds opening 45 and has a fiat horizontal top surface 37awhich provides the primary support for the thrower. From Fig. 9 it will be observed that a portion of the top surface of pad 36 as at 36c is elevatcd slightly above top surface 37a of pad 37. Surface 37a in turn is disposed at a higher level than bottom' surface 33a of slot 33in sidewall 29 of the head.

When it is desired to move the lock from locking position, as shown in Fig. l, to lock-set position as shown in Fig'g-S, to-permit opening of the knuckle, the-uncouplin'grod (not shown) is actuated, thereby rotating rotor member 59. This causes rotor lever 57 to pivot, which raises lifter link 54 so that trunnion 55 is moved to the upper end of slot56 in the'lock leg. Simultaneously, the upper end'61-of link 54*is withdrawn from its antic'reep position beneath theknuckle tail and further r0tation of member 59 raises the lock out of locking position toaposition in whichthe lock-set seat 62 on the lock is above the rearward arm 34 of the knuckle thrower. The uncouplingrod is then released and the lock drops to :the position in which its lock-set seat 62 rests on the lock seating surface 64 on arm 34, as shown' in Fig. 5. Thus in lock-set position the lock is supported on the knuckle thrower and consequently the thrower is rockedforwardly generally about line x-x until arm34 rests on surface 33a in recess 33 (Figs. 2 and 7).

Fig. 7, therefore, represents the position of the knuckle throwerwhen the lock is in either locked or lock-set position. As mentioned before, for purposes of clarity, the lock has not been shown in this view but the thrower is shown in the position assumed by it when the lock is resting thereon: It will be noted in Fig. 7 that the forward arm 40 of the knuckle thrower rests only on the forward edge of pad 36', as at 36d. It will also be noted that the bottom bearing surface 6601 the thrower, which lies adjacent lower-trunnion 43, engages pad 37 as at 3712 and slopes upwardly from this seat'in a generally rearward direction from point 37b. Sufiicient clearance is provided for lower trunnion 43in opening 45 so as to accommodate tilting of the trunnion as the thrower is rocked.

When the lock of one of two-coupled couplers is placed on lock-set position (Fig. 5) and the knuckle of that conpler-begins to open as the couplers are moved apart, the lock bearing surface '38:! on the knuckle tail 39 engages bottom bearing surface 68 on the lock and moves the lock in a'forward and upward direction to take it off lock-set position. As soon as the weight of the lock is removed from rearward arm 34 of the knuckle thrower, the thrower rock's rearwardly generally about line xx to its reposed position (Figs; 6 and 8). In this position of the thrower it will be observed 'in Fig. 8 that arm 40 is in full contact with. the top surface 36b of pad 36. Portion H of the thrower has moved downward toward bottom wall 31 while at the same time thrower arm 34 has moved upward, away from bottom surface 33a of slot 33 so that a snbstantial clearance as at 70 exists between the underside of this arm and the bottom wall of the slot.

Referringfto Fig. 6, which shows theknuckle of the coupler infully opened position, it will be noted that with the thrower in reposed position the lock-set seating surface 64011 rearward arm 34 has been raised substantially abovethe lock-set seat 62 on lock 18. Although a por- I tion of this difference in elevation is caused by the downward movement of the lock as it progresses along the downwardly inclined bearing surface 38 on the knuckle tail, even without this downward movement of the lock on the knuckle tail, the upward movement of rearward arm 34 resulting from the rearward rocking of the thrower is sufficient to prevent the lock from inadvertently being thrown back to lock-set position.

It will be understood that with bearing surface 360 of bearing pad 36 at a higher elevation than bearing surface 37a of pad 37, the horizontal bottom bearing surface 66 on the thrower is prevented from fully seating on horizontal surface 37a. Since the center of gravity G of the thrower is disposed within the extremities of surface 37a on bearing pad 37, there would be no tendency for the knuckle thrower to rock rearwardly from surface 37a if the bottom bearing surface 66 on the knuckle thrower were in full surface contact with surface 37a. By forming surface 360 at a higher elevation than surface 371: and thereby removing the support from beneath that portion of surface 66 in the vicinity of the center of gravity of the knuckle thrower, the thrower tends to. rock rearwardly from its two supporting surfaces 360 and 37a. This rearward rocking of the thrower causes the lock-set seating surface on arm 34 of the thrower to be raised additionally above that which would occur if the thrower merely rocked back to a horizontal position.

It will be apparent that since the rearward tipping of the thrower from its supporting surfaces 360 and 37a is due to the removal of the support from beneath the center of gravity of the thrower, for purposes of the invention, seat 37 need not be of the same form shown and described. It is an essential requirement, however, that these supporting surfaces be so disposed that the center of gravity of the thrower is located intermediate these surfaces and rearwardly of a line connecting these surfaces.

Furthermore, it will be seen that bottom surface 33a of recess 33 must be located below surface 37a of seat 37 in order that the thrower be able to rock forwardly when the lock is in lock-set position. When these conditions are present the thrower will lie in a forwardly rocked position when the lock rests on the thrower and will rock rearwardly to its reposed position when the lock is removed from the thrower. The actual magnitude of the difference in elevation between surfaces 360, 37a and 33a may, of course, be varied within the necessary requirements for clearance between the individual parts of the coupler.

It is apparent that the tipping of this thrower rearwardly from its supporting surfaces in the coupler head is limited by the contact between upper trunnion 42 and bearing surface 44a on lug 44 and between lower trunnion 43 and the surface of opening 45 as at 45a. Any increase in clearance between these trunnions and the engaged surfaces resulting from wear will allow the thrower to tip rearwardly an even greater amount than before, thereby raising the lock-set seating surface 64 to a higher elevation. Accordingly, the operation of my invention tends to improve as the coupler is used in service.

Referring to Fig. 9, which shows the position of the thrower with respect to the coupler head after the lock has been taken off lock-set position, it will be seen that the bearing pad 36 slopes downwardly lengthwise of the pad starting from side wall 28 of the coupler head. As has been previously stated, the lock, as it is being taken off lock-set position by the opening of the knuckle, tends to drag the rearward arm 34 of the thrower forwardly and consequently move seat 64 closer to seat 62 on the lock. This undesired forward movement of arm 34 is resisted by the downwardly sloped surface of pad 36 which is engaged by thrower arm 40 and opposes rotation of the thrower. It will be apparent that arm 40 must move uphill on pad 36 in order to effect rotation of the thrower. This uphill relationship, however, prevents rotation of the thrower and the consequent forward movement of arm 34. In Fig. 6 which shows the positions of the thrower and the lock when the knuckle is in fully opened position, it can be' seen that in addition to the difference in elevation existing between the lock-set seat on the lock and the lock seating surface on the thrower, a longitudinal clearance, as at 72, exists between these parts. This combination of a difference in elevation and a longitudinal clearance ensures that the lock will not inadvertently be thrown back to lock-set position.

.It will be seen that by moving the bearing pad 36 forwardly or rearwardly from the position shown the general position of the axis xx about which the thrower rocks is likewise moved forwardly or rearwardly and the tendency for the thrower 20 to rock rearwardly when the weight of the lock is removed therefrom can be increased or decreased. Accordingly, in order to assure a definite rearward rocking of the thrower about axis xx when the weight of the lock is removed, the bearing pad 36 must be located in the interior chamber so as to underlie the forward portion of forward arm 40 of the thrower. The sloping of the top surface of pad 36 downwardly toward the rearward end of the pad, as at 36b, also ensures that the general position of axis xx will remain as far forwardly in the coupler head as possible. It will be seen from Fig. 8 that if the top surface of pad 36 was horizontal at 36b instead of sloping downwardly, the thrower would rock about the rearward edge of this surface as it moved to its reposed position and accordingly its tendency to rock rearwardly would be decreased.

While the invention has been shown applied to the coupler known as the proposed A. A. R. type F interlocking coupler, it should be understood that the invention is not restricted to use with this particular coupler but can be utilized in other knuckle-type couplers of similar construction and operation.

The terms and expressions which I have employed are used as terms of description and not of limitation, and I have no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof, but recognize that various modifications are possible within the scope of the invention claimed.

I claim:

1. A car coupler head comprising top, bottom and side walls forming a knuckle-receiving chamber therebetween, one of said side walls having a slot for receiving the end of an associated knuckle thrower, said bottom wall of said head having a pair of pads for supporting the thrower in said head, one of said pads being disposed at a higher elevation than the other of said pads, both of said pads being'at a higher elevation than the bottom surface of said slot.

2. A car coupler head comprising top, bottom and side walls forming a chamber therebetween, one of said side walls having a slot therein, said slot having a bottom surface for engagement with the end of an associated knuckle thrower, said bottom wall of said head having means thereon for supporting the thrower in said head, said means and said bottom surface being laterally disposed in said head and progressively decreasing in elevation from one of said side walls to the other of said side walls.

3. In a car coupler, a head, a knuckle pivoted to said head, a movable lock for said knuckle, a generally vertically rockable knuckle thrower pivoted to said head, said thrower comprising a rearward arm having a surface thereon for engagement with a lock-set seat on said lock when said lock is in lock-set position, said head having a recess in a side wall thereof for receiving the end of said rearward arm, a pair of generally horizontally spaced pads in said head for supporting said thrower, said pads being elevated above the bottom surface of said recess, the center of gravity of said thrower being disposed generally intermediate said pads and rearwardly of an axis extending between said pads whereby said thrower when unencumbered in said head rocks about said axis to a rearwardly tipped position, said thrower rocking to a for- 7 Wardly tipped position when said lock is insaid lock-set positionI 4. In a car coupler, a head havinga guard arm on: one side thereof, a knuckle pivoted to said head, a lock for said knuckle, a knucklethrower pivoted to said head, said thrower having an arm for'supporting said'lo'ck inlock-set position, means in said head for underlying said thrower and rockably supporting the same in said head, said head having a recess in said guard arm side thereof to receive said arm,-said thrower being in a forwardly rocked position in which said arm engages the bottom surface of said recess when said lock is in said lock-set position, said thrower assuminga rearwardly rocked position-in which said arm is elevated above said bottom surface when said lock is moved oif said lock-set'p o'sition.

5. A car-coupler head comprising top, bottom and side Walls forming a chamber therebetween, said bottom wall:

having an opening therein for receiving the trunnion of an associated knuckle thrower, a raised seat surrounding said-opening, a bearing padextending laterally into said chamber from one ofsaid side walls, the top surface of said pad being sloped downwardly in a generally-rearward direction, said pad and said seat being so spacedlaterally in said head relative to the center of gravity'of the associated thrower as to underlie and rockably support the thrower in said head.

6. A car coupler head comprising top, bottom and side walls forming a chamber therebetween, said bottom wall.

having a plurality. of raised bearing surfaces for rockably supporting an associated pivoted knuckle thrower in said head, one of said surfaces extending from one of said side walls into said chamber in a generally diagonally rearward direction and being sloped rearwardly in a downward direction commencing at the forward extremity of said surface.

7. In a car coupler, a head, a knuckle pivoted to said head, a knuckle thrower pivoted to said head, a movable lock for said knuckle, said thrower having a surface thereon adapted for engagement with a lock-set seat on said lock when said lock is in lock-set position, said knuckle having a tail portion to engage said lock and move the latter off said lock-set position during opening of said knuckle, said head having support means about which said thrower rocks rearwardly when said lock is taken off said lock-set position by said tail of said knuckle to position said surface above said lock-set seat on said lock.

8. In a car coupler, a head, a knuckle pivoted to said head, said knuckle having a rearwardly extending tail portion, a movable lock for said knuckle, a knuckle thrower having a lock-set seating surface for engagement with'a lock-set seat on said lock to support said lock in lock-set position, said tail portion having means for moving said lock off said lock-set position upon movement of said knuckle to open position, said tail portion havinga top surface sloped downwardly in a direction transversely of the coupler for sliding engagement with said lock when said lock has been taken off said lock-set position, said sloping top surface causing said lock to move progressively lower when said knuckle is swung to open position.

9. In a car coupler, a head comprising a bottomwall, a knuckle pivoted to said head, a generally vertically rockable knuckle thrower mounted in said head for pivotal movement in a generally horizontal plane, said head having generally horizontally spaced support means underlying said thrower and supporting the same above said wall, the center of gravity of said thrower being disposed generally intermediate said means and rearwardly of an axis extending between said means, said thrower being rockable in a generally vertical direction about said axis.

10. In a car coupler, a head, a knuckle pivoted to said head, a lock for said knuckle and a generally vertically rockable knuckle thrower having an arm for supporting said lock in locking and in lock-set position, said head having a .plurality'of generally horizontally spaced means for supporting said thrower, certain ofsaid means being disposed at different elevationsin saidhead, the center of gravity of said thrower being disposed generally between said certainof said means and rearwardly of an axis passing through said last mentioned means, said thrower when said lock is in locking or lock-set position being caused by the weight of said lock to rock forwardly generally about said axis and move said arm into engagement with other of said means, the weight of said thrower when said lock is moved out of locking or lock-set position causing said thrower to rock rearwardly generally about said'axis to a position in which saidarm is ele-' vated with respect to said otherfof said means.

11. In a car coupler,a head having a bottom wall and and a side wall, a knuckle pivotally mounted on said head, a generally horizontally extending knuckle thrower pivotally mounted on said bottom wall and being rockable in a generally vertical direction, said thrower having'a forwardly extending arm for engaging said knuckle to open the same upon predetermined pivotal movement of said thrower, an elevated bearing pad on said bottom wall extending inwardly from said side wall, said pad underlying said arm and comprising a support for said thrower, the center of gravity of said thrower being disposed generally between said pad and supporting portion of said bottom Wall and rearwardly of an axis extending therebetween, the weight of said thrower when the latter is unencumbered in said head causing the thrower to rock about said axis to a rearwardly tipped position in said head.

12. In a car coupler, a head, a knuckle'pivoted to said head, a knuckle thrower having a vertical trunnion, said head having a bottom wall with an opening therein for receiving said trunnion for pivotal mounting of said thrower, said thrower comprising a forward arm, raised pad means on said bottom wall of the head underlying said thrower and supporting the same adjacent said opening and beneath the forward end of said arm, thecenter of gravity of said thrower being disposed generally intermediate said pad means and rearwardly of an axis extending therebetween, said thrower being rockable in a generally verticaldirection about said axis.

13. In a car coupler, a headahaving abottom wall, a knuckle pivoted to said head, a movable lock for said knuckle, a generally vertically rockable knuckle thrower pivoted to said head, said thrower comprising a rearward arm having a seat thereon adapted for engagement with a lock-set seat on said lock to support the latter in lockset position, said head having a surface for supporting the end portion of said rearward arm, a pair of raised generally horizontally spaced bearing surfaces on said bottom wall of said head for supporting the thrower in said head, one of said bearing surfaces being elevated above the other of said bearing surfaces, both of said surfaces being disposed at a higher elevation than said first-named surface, the center of gravity of said thrower being disposed generally between said bearing surfaces and rearwardly of an axis extending between said bearing surfaces, the weight of said thrower when said lock is removed from supported engagement with said arm causing the thrower to rock rearwardly about said axis to a position in which said arm is elevated with respect to said first-named surface, said thrower when said lock is placed in said lock-set position rockingforwardly generally about said axis to a position in which said arm is in contact with said first-named sur face.

14. In a car coupler, ahead, a knuckle pivoted to said head, a knuckle thrower adapted for rockable movement in a generally vertical direction in said head,said head having a recess in a wall thereof for receiving an end portion of said thrower, said recess having a bottom surface engageable by said end portion when the thrower is in a forwardly rocked position in said head, generally diagonally spaced pads in said head underlying and supporting said thrower, the top surfaces of said pads being disposed at a higher elevation than said bottom surface of said recess, the center of gravity of said thrower being disposed generally intermediate said pads and rearwardly of an axis extending between said pads, the weight of said thrower when the latter is unencumbered causing the thrower to rock about said axis to a rearwardly tipped position in said head.

15. In a car coupler, a head, a knuckle thrower pivoted to said head, forward and rearward means in said head for rock'ably supporting said thrower, the center of gravity of said thrower being disposed generally intermediate said means and re-arwardly of an axis passing through said means whereby said thrower rocks about said axis to a rearwardly tipped position when unencumbered in said head, said forward means having a top surface sloped rearwardly and downwardly so that said thrower engages the forward edge of said surface.

16. In a car coupler comprising a head, said head having side walls and a bottom wall partially defining a chamber therebetween, a knuckle pivoted to said head, a knuckle thrower having a vertical trunnion extending downwardly therefrom, said bottom wall having an opening therein loosely receiving said trunnion therein for pivotally mounting said thrower in said head, a pair of raised pad portions on said bottom wall underlying said thrower and supporting the same above said bottom wall, one of said pad portions being disposed adjacent one of said side walls and the other of said pad portions being disposed adjacent said opening, said thrower being rockable in a generally vertical direction about an axis passing through said pad portions, said axis being located generally forwardly of the center of gravity of said thrower, the weight of said thrower causing the latter when unencumbered to rock to a rearw-ardly tipped position in said head.

References Cited in the file of this patent UNITED STATES PATENTS 872,454 Ritter Dec. 3, 1907 1,021,465 Kelso Mar. 26, 1912 1,157,496 Blackman Oct. 19, 1915 1,932,439 Bazely Oct. 31, 1933 2,023,550 Richards Dec. 10, 1935 2,170,891 Bazely Aug. 29, 1939 2,646,896 Metzger July 28, 1953 2,695,714 Kayler Nov. 30, 1954 

